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81.
It is known that regular aerobic exercise enhances cognitive functions and increases blood insulin-like growth factor 1 (IGF-1) levels. People living in urban areas spend most of their time indoors and indoor air quality can affect health. We investigated the effects of aerobic exercise in poor and good air quality environments on hippocampus and prefrontal cortex (PFC) neurons, anxiety, and spatial learning and memory in adolescent mice. Poor air quality impaired spatial learning and memory; exercise did not affect learning or memory impairment. Exercise in a good air quality environment improved spatial learning and memory. Poor air quality increased apoptosis in the hippocampus and PFC. Both exercised and sedentary groups living in a poor air quality environment had lower serum IGF-1 levels than those living in a good air quality environment. Living in a poor air quality environment has negative effects on the hippocampus, PFC and blood IGF-1 levels in adolescent mice, but exercise did not alter the negative effects of poor air quality.  相似文献   
82.
Anxiety and depression are common in diabetics. Diabetes also may cause reduced leptin levels in the blood. We investigated the relation between diabetes induced anxiety- and depression-like behavior, and leptin and leptin receptor expression levels in diabetic rats. The anxiety- and depression-like behaviors of rats were assessed 4 weeks after intraperitoneal injection of streptozotocin. Diabetic rats exhibited greater anxiety-like behavior; they spent more time in closed branches of the elevated plus maze test and less time in the center cells of the open field arena. Increased depression-like behavior was observed in diabetic rats using the Porsolt swim test. Prefrontal cortex (PFC), blood leptin levels and PFC neuron numbers were decreased, and leptin receptor expression and apoptosis were increased in diabetic rats. Blood corticosterone levels also were increased in diabetic rats. These results indicate that reduction of leptin up-regulates leptin receptor expression and may affect PFC neurons, which eventually triggers anxiety- and depression-like behaviors in diabetic rats.  相似文献   
83.
A search for noncanonical variants of the gypsy retrotransposon (MDG4) in the genome of the Drosophila melanogaster strain G32 led to the cloning of four copies of the poorly studied 7411-bp gtwin element. Sequence analysis showed that gtwin belongs to a family of endogeneous retroviruses, which are widespread in the Drosophila genome and have recently been termed insect erantiviruses. The gtwin retrotransposon is evolutionarily closest to MDG4, as evident from a good alignment of their nucleotide sequences including ORF1 (the pol gene) and ORF3 (the env gene), as well as the amino acid sequences of their protein products. These regions showed more than 75% homology. The distribution of gtwin was studied in several strains of the genus Drosophila. While strain G32 contained more than 20 copies of the element, ten other D. melanogaster strains carried gtwin in two to six copies per genome. The gtwin element was not detected in D. hydei or D. virilis. Comparison of the cloned gtwin sequences with the gtwin sequence available from the D. melanogaster genome database showed that the two variants of the mobile element differ by the presence or absence of a stop codon in the central region of ORF3. Its absence from the gtwin copies cloned from the strain G32 may indicate an association between the functional state of ORF3 and amplification of the element.  相似文献   
84.
The tumour microenvironment and genetic alterations collectively influence drug efficacy in cancer, but current evidence is limited and systematic analyses are lacking. Using chronic lymphocytic leukaemia (CLL) as a model disease, we investigated the influence of 17 microenvironmental stimuli on 12 drugs in 192 genetically characterised patient samples. Based on microenvironmental response, we identified four subgroups with distinct clinical outcomes beyond known prognostic markers. Response to multiple microenvironmental stimuli was amplified in trisomy 12 samples. Trisomy 12 was associated with a distinct epigenetic signature. Bromodomain inhibition reversed this epigenetic profile and could be used to target microenvironmental signalling in trisomy 12 CLL. We quantified the impact of microenvironmental stimuli on drug response and their dependence on genetic alterations, identifying interleukin 4 (IL4) and Toll‐like receptor (TLR) stimulation as the strongest actuators of drug resistance. IL4 and TLR signalling activity was increased in CLL‐infiltrated lymph nodes compared with healthy samples. High IL4 activity correlated with faster disease progression. The publicly available dataset can facilitate the investigation of cell‐extrinsic mechanisms of drug resistance and disease progression.  相似文献   
85.
Granular cell tumours (GCT) of the soft tissues are rare benign tumours but some time may be difficult to distinguish from malignant neoplasms. It is important that clinicians are aware of their existence. We present a new case of GCT of the soft tissues followed by a brief review of literature.  相似文献   
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Protein genes Ag85A, Esat-6, and Cfp10 of Mycobacterium tuberculosis were sequenced using the database GenBank to implement selection and synthesis of primer pairs of given genes. PCR was used to obtain target amplicons of the genes. Chromosome DNA of M. tuberculosis H37Rv was used as the DNA amplification matrix. The PCR products were obtained using the plasmid pQE6, cloned, and amplified in the Escherichia coli M15 strain. Chimere products containing mycobacterial genes and cellulose binding protein domain (CBD), were obtained using the plasmid treated with restriction endonucleases. CBD fragment obtained using similar treatment of the ptt10 plasmid. The plasmids containing merged sequences of mycobacterial genes-antigenes and CBD were selected. The 3 mycobacterial genes were expressed in the E. coli M15 cells resulting in biosynthesis of corresponding recombinant proteins of expected molecular weight. Concentration of CBD, Cfp10-CBD, Ag85A-CBD, and ESAT6-CBD was 20%, 15%, and 15% total protein, respectively. The resulting chimere proteins provide high affinity for cellulose and high stability. Immobilization of CBD-containing recombinant proteins proceeds as one-stage process providing target protein purification and adsorption on cellulose. The vaccines produced using this technology are inexpensive because of low cost of cellulose sorbents as well as simultaneous use of cellulose for purification and immobilization of protein. Many cellulose preparations are not toxic, biocompatible, and widely used in medicine.  相似文献   
89.
Cultures of Achlya sp., Phytophthora cinnamomi, Saprolegnia diclina, S. ferax, and S. parasitica, treated with 6-carboxyfluorescein diacetate solution, accumulate 6-carboxyfluorescein in a reticulate system of fine tubules. The network shows longitudinal polarity within the hyphae, tubules being finest toward the hyphal tips. In more mature subapical regions the network is connected with large vacuoles that also accumulate 6-carboxyfluorescein. A morphologically similar system has also been identified in freeze-substituted hyphae of S. ferax. The network is considered to be vacuolar, but differs from the tubular vacuole system of true fungi in that tubules are less motile, more frequently branched, and do not alternate with clusters of spherical vacuoles. The appearance of the network resembles patterns of calcium-sensitive dye staining and it is suggested that the vacuolar reticulum in the tip region of oomycete hyphae may act as a Ca2+ sink. The tubular reticulum in oomycetes is very fragile and can be shown with 6-carboxyfluorescein in only those hyphal tips with a motility and organelle distribution characteristic of growing hyphae with normal morphology. Diverse abnormal hyphae show a range of other fluorochrome localizations. These include large irregular compartments filled with fluorochrome, and fluorescent cytoplasm with organelles and vacuoles standing out in negative contrast. These localizations in abnormal hyphae are correlated with other structural changes indicative of damage. Special care is required in experiments with oomycetes to avoid such artefacts of localization. Copyright 1997 Academic Press. Copyright 1997 Academic Press  相似文献   
90.
Cadmium and zinc share many similar physiochemical properties, but their compartmentation, complexation and impact on other mineral element distribution in plant tissues may drastically differ. In this study, we address the impact of 10 μm Cd or 50 μm Zn treatments on ion distribution in leaves of a metallicolous population of the non‐hyperaccumulating species Zygophyllum fabago at tissue and cell level, and the consequences on the plant response through a combined physiological, proteomic and metabolite approach. Micro‐proton‐induced X‐ray emission and laser ablation inductively coupled mass spectrometry analyses indicated hot spots of Cd concentrations in the vicinity of vascular bundles in response to Cd treatment, essentially bound to S‐containing compounds as revealed by extended X‐ray absorption fine structure and non‐protein thiol compounds analyses. A preferential accumulation of Zn occurred in vascular bundle and spongy mesophyll in response to Zn treatment, and was mainly bound to O/N‐ligands. Leaf proteomics and physiological status evidenced a protection of photosynthetically active tissues and the maintenance of cell turgor through specific distribution and complexation of toxic ions, reallocation of some essential elements, synthesis of proteins involved in photosynthetic apparatus or C‐metabolism, and metabolite synthesis with some specificities regarding the considered heavy metal treatment.  相似文献   
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